syzbot


possible deadlock in hfs_find_init

Status: upstream: reported C repro on 2023/03/22 23:14
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+5ec6d29e9352c6f10dc7@syzkaller.appspotmail.com
First crash: 996d, last: 7d12h
Fix bisection: failed (error log, bisect log)
  
Bug presence (1)
Date Name Commit Repro Result
2024/04/24 upstream (ToT) e88c4cfcb7b8 C [report] possible deadlock in hfs_find_init
Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 possible deadlock in hfs_find_init hfs 4 C 1 1019d 1051d 0/1 upstream: reported C repro on 2023/01/26 19:14
linux-4.19 possible deadlock in hfs_find_init hfs 4 C error 7 1013d 1079d 0/1 upstream: reported C repro on 2022/12/30 06:08
linux-6.6 possible deadlock in hfs_find_init origin:upstream 4 C 41 1d14h 178d 0/2 upstream: reported C repro on 2025/06/17 20:55
upstream possible deadlock in hfs_find_init (2) hfs 4 C error 5847 3h38m 1082d 0/29 upstream: reported C repro on 2022/12/27 00:59
linux-6.1 possible deadlock in hfs_find_init origin:upstream 4 C 281 2h26m 998d 0/3 upstream: reported C repro on 2023/03/20 17:38
upstream possible deadlock in hfs_find_init hfs 4 C done error 1 1800d 2791d 20/29 fixed on 2021/11/10 00:50
Last patch testing requests (10)
Created Duration User Patch Repo Result
2025/11/18 02:05 10m retest repro linux-5.15.y report log
2025/11/18 02:05 10m retest repro linux-5.15.y report log
2025/11/18 02:05 10m retest repro linux-5.15.y report log
2025/11/18 02:05 10m retest repro linux-5.15.y report log
2025/10/18 05:47 15m retest repro linux-5.15.y report log
2025/10/03 19:53 14m retest repro linux-5.15.y report log
2025/10/03 19:53 39m retest repro linux-5.15.y report log
2025/09/02 16:44 9m retest repro linux-5.15.y report log
2025/09/02 16:44 9m retest repro linux-5.15.y report log
2025/09/02 16:44 9m retest repro linux-5.15.y report log

Sample crash report:
WARNING: The mand mount option has been deprecated and
         and is ignored by this kernel. Remove the mand
         option from the mount to silence this warning.
=======================================================
============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.0.17/4321 is trying to acquire lock:
ffff88802507c0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1

but task is already holding lock:
ffff88802507c0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&tree->tree_lock/1);
  lock(&tree->tree_lock/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by syz.0.17/4321:
 #0: ffff88802507a460 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
 #1: ffff88807e0e02a8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff88807e0e02a8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: generic_file_write_iter+0x7e/0x1b0 mm/filemap.c:3941
 #2: ffff88807e0e00f8 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xd7/0x1280 fs/hfs/extent.c:397
 #3: ffff88802507c0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1
 #4: ffff888021de00f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xd7/0x1280 fs/hfs/extent.c:397

stack backtrace:
CPU: 0 PID: 4321 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 __lock_acquire+0x1227/0x7c60 kernel/locking/lockdep.c:-1
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_extend_file+0x2eb/0x1280 fs/hfs/extent.c:401
 hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:231
 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x313/0x1280 fs/hfs/extent.c:401
 hfs_get_block+0x3d4/0xbd0 fs/hfs/extent.c:353
 __block_write_begin_int+0x54e/0x15a0 fs/buffer.c:2012
 __block_write_begin fs/buffer.c:2062 [inline]
 block_write_begin fs/buffer.c:2122 [inline]
 cont_write_begin+0x58a/0x7b0 fs/buffer.c:2471
 hfs_write_begin+0x92/0xe0 fs/hfs/inode.c:59
 cont_expand_zero fs/buffer.c:2398 [inline]
 cont_write_begin+0x26c/0x7b0 fs/buffer.c:2461
 hfs_write_begin+0x92/0xe0 fs/hfs/inode.c:59
 generic_perform_write+0x2aa/0x530 mm/filemap.c:3785
 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x712/0xd00 fs/read_write.c:594
 ksys_pwrite64 fs/read_write.c:701 [inline]
 __do_sys_pwrite64 fs/read_write.c:711 [inline]
 __se_sys_pwrite64 fs/read_write.c:708 [inline]
 __x64_sys_pwrite64+0x194/0x220 fs/read_write.c:708
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff121b53ba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffa49aee08 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007ff121d9afa0 RCX: 00007ff121b53ba9
RDX: 000000000000ff10 RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007ff121bd6e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000008000c61 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff121d9afa0 R14: 00007ff121d9afa0 R15: 0000000000000004
 </TASK>

Crashes (189):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/15 06:08 linux-5.15.y 43bb85222e53 e2beed91 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/02/23 22:00 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2024/12/30 04:22 linux-5.15.y 91786f140358 d3ccff63 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2024/04/09 10:28 linux-5.15.y 9465fef4ae35 f3234354 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2023/07/23 02:21 linux-5.15.y d54cfc420586 27cbe77f .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2024/06/12 05:04 linux-5.15.y c61bd26ae81a 4d75f4f7 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2023/06/17 03:50 linux-5.15.y 471e639e59d1 f3921d4d .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/12/05 19:00 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/11/24 10:58 linux-5.15.y cc5ec8769306 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/11/03 11:20 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/10/30 19:17 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/10/27 05:57 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/10/26 16:38 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/09/19 04:47 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/09/18 18:54 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/09/17 05:36 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/09/16 19:35 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/09/15 05:08 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/09/08 11:00 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/08/18 03:14 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/08/17 21:48 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/08/17 20:38 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/08/17 05:18 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/08/11 16:21 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/08/11 12:48 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/07/30 20:57 linux-5.15.y c79648372d02 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/07/21 13:29 linux-5.15.y c79648372d02 56d87229 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/07/20 20:12 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/06/29 11:00 linux-5.15.y 3dea0e7f549e fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/06/17 16:25 linux-5.15.y 1c700860e8bc cfebc887 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/06/13 18:04 linux-5.15.y 1c700860e8bc 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/05/28 10:48 linux-5.15.y 98f47d0e9b8c 874a1386 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/05/19 11:45 linux-5.15.y a68c15152131 b84f0537 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/05/11 17:42 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_find_init
2025/08/17 10:45 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/08/08 20:30 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/08/07 16:18 linux-5.15.y c79648372d02 04cffc22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/08/05 04:27 linux-5.15.y c79648372d02 f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/08/03 22:49 linux-5.15.y c79648372d02 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/07/25 17:19 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/07/21 07:00 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/07/20 23:24 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/07/20 21:51 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/07/20 16:15 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/06/13 08:45 linux-5.15.y 1c700860e8bc 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/06/10 15:43 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/06/05 21:37 linux-5.15.y 1c700860e8bc 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/06/05 11:23 linux-5.15.y 1c700860e8bc 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/06/04 10:51 linux-5.15.y 98f47d0e9b8c e565f08d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/06/02 01:51 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/05/29 04:33 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/05/16 08:55 linux-5.15.y 3b8db0e4f263 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/05/12 01:29 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/05/10 21:40 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/05/10 14:49 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2025/05/05 07:43 linux-5.15.y 16fdf2c7111b b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2023/03/22 23:13 linux-5.15.y 115472395b0a f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
* Struck through repros no longer work on HEAD.